Chair structure



Jul-Y 1963 H. c. BANKE 3,099,479

CHAIR STRUCTURE Filed Feb. 27, 1961 3 Sheets-Sheet 1 g5 Jmhfjm H. C.BANKE CHAIR STRUCTURE July 30, 1963 5 Sheets-Sheet 2 Filed Feb. 27. 1961July 30, 1963 H. c. BANKE 3,099,479

CHAIR STRUCTURE Filed Feb. 27, 1961 5 Sheets-Sheet 3 Wf/W gj lOO +7, Ia-8 93 @Z United States Patent 3,899,479 CHAlllR STRUCTURE Henry C.Banks, Chicago, llll., assiguor to Clarin Mfg. (10., Chicago, ill, acorporation of Illinois Filed Feb. 27, 1361, Ser. No. 91,695 2 Claims.(Cl. 297-36) The present invention relates to a chair with a tablet arm,and more particularly to structure for more effectively mounting such atablet arm on a l air.

The tablet arm for a chair is generally a flat member attached to thechair and positioned so that the person seated in the chair may use itto support materials, and in particular, as a writing surface. This is auseful and convenient way of providing these facilities with obvioussaving in expense and space, and chairs with tablet arms are used agreat deal in schools, lecture halls and the like. Of course, it ishighly desirable that the tablet arm be firmly supported during use,even after a period of service which involves repeated raisings andlowerings, so that it will provide a solid stable surface on which towrite. At the same time, it is desirable that the structure operate incramped quarters, i.e., move so as to avoid interference with adjacentchairs. It is further desirable that the person who will be using thechair can easily and quicldy tilt the arm to get in and out of the chairand can lower it when the tablet arm is not needed. Further, in additionto simplicity of operation, the operation should be as smooth and quietas possible, and while a of effort should be required, jammed fingersand bruised shin bones can result from a completely free swinging arm.

Accordingly, the principal object of the present invention is to providean improved chair with tablet arm. More specific objects includeproviding such a chair which more effectively combines easy and simpleoperation with firm and stable support. In this connection, an object isto provide operation which is directly pressure responsive and does notrequire preliminary unlocking or other preparatory steps. A furtherspecific object is to provide such an improved chair having a tablet armwhich, while easy to move, is provided with restraining means whichprevents the arm from falling and thereby create noise and possibleinjury. It is another object to provide such .a structure which isdurable and sturdy, yet economical.

Further objects and advantages will become obvious from the followingdescription and accompanying drawings (3 sheets).

In the drawings:

FIGURE 1 is a perspective view of a folding chair having a tablet armand embodying various features of the invention, the chair beingextended and the arm being shown in phantom in its raised or operativeposition;

FIGURE 2 is similar to FIG. 1, with the arm in a lowered position;

FIGURE 3 is a front view (with parts broken away) of the chair structureshown in FIG. 1, with the chair folded and the arm in the storageposition;

FIGURE 4 is a side view of the chair structure shown in FIG. 3;

FIGURE 5 is an enlarged fragmentary front view (with parts broken awayand in section), showing the front connection means between the tabletarm and the support member of the chair shown in FIG. 1, the arm beingin the raised position;

FIGURE 6 is generally similar to FIG. 5, the arm being in a loweredposition;

FIGURE 7 is a sectional view taken generally along line 7--7 of FIG. 6;

FIGURE 8 is a sectional view taken generally along "ice 2 line 8-8 ofFIG. 5, showing the pressure responsive locking means;

FIGURE 9 is a view parts broken away and in section) taken generallyalong line 99 of FIG. 5.

FIGURE 10 is an enlarged perspective view of the double-pivot bracket ofthe tablet arm front connection means;

FIGURE 11 is an enlarged perspective View of the sleeve bracket of thefront connection means, together with the associated roller sleeve andthe spring and ball bearings of the pressure responsive means;

FIGURE 12 is an enlarged perspective View of a mounting bearing for thetablet arm support member; and

FIGURE 13 is an enlarged perspective view of the rear support bracketfor the tablet arm, as viewed when the tablet arm is lowered alongsidethe Briefly, the illustrated chair 21 includes a frame on which a tabletarm 25 is mounted for ready movement between a firmly supported raisedor use position (FIG. 1) and a lowered or non-use position (FIG. 2), themovement being accomplished by first tilting the arm and then swingingit downwardly. Pressure responsive locking or holding means 27releasably maintain the arm 25 in the raised position until sufiicientlyand properly directed pressure is applied to the arm to move it to alowered position. No preliminary unlatching, unbolting, or the like isrequired to lower the Retarding means 29 are also provided to preventthe arm from falling from the tilted position to a lowered position(FIG. 2). The illustrated chair 21 may itself be folded, and the tabletarm 25 then moved relative to the chair into a storage position (FIGS. 3and 4).

The present invention has application to various types of chairs,including rigid structures, but since it is especially advantageous foruse in a folding chair, it will be described in connection with afolding chair 21.

The illustrated folding chair 21 comprises a conventioual construction,generally similar to that shown in United States Patent No. 2,548,098issued April 10, 1951. As shown in FIGS. 1 through 4, the chair 21comprises a frame including an inverted, generally U-shaped section 23which is formed from a strip of metal that has had its lateral edgesrolled inwardly to form parallel beads with a flat portion in between.The bight portion of the section 23 supports a chair back rest 31, andthe downwardly extending portions provide a pair of front legs 33 forthe chair. The front legs 33 are interconnected a short distance fromtheir lower ends by a cross brace 35 of a similar construction to thatof the section 23. The cross brace 35 is preferably rigidly and firmlysecured to the legs 33 by welding, bolting, or the like, as it providessupport for the tablet arm 25 in a manner to be described. A pair ofrear legs 37 of similar construction to the front legs 33 are pivotallyconnected to them, as indicated at 39, to form an X construction oneither side of the chair 21. The rear legs 37 may be reinforced byhaving a pair of cross braces 49 connected between them. The upper endsof the rear legs 37 are pivotally connected to either side of a chairseat 41. The seat 41 is further pivotally supported by a pair of links43 which are in turn pivotally connected to the section 23. Furthersupport is provided for the seat 41, when the chair 21 is in theextended position shown in FIGS. 1 and 2, by a cross brace 45 connectedbetween the front legs 33 above the pivots 39. The construction justdescribed permits the chair 21 to be folded so that the upper surface ofthe seat 41 faces forwardly when the chair is folded into the positionshown in FIGS. 3 and 4. The ends of the legs 33 and 37 are each providedwith a pad 47 of a suitable material, such as rubber or plastic.

The illustrated tablet arm 25 is a generally elongated platform or platemade of wood or other suitable material. It is formed so that, when itis in the raised or use position shown in FIG. 1, with its upper surfacelying in a generally horizontal plane, its forward end, which 18enlarged relative to its rearward portion, provides a writing surface,while the rearward portion provides an arm rest while affording ampleroom for the occupant of the chair.

In the illustrated device, the tablet arm is pivotally connected at itsrearward end to the upper portion of the section 23 by a rear supportmeans in the form of a bracket 49 (shown particularly in FIG. 13), andit is also pivotally connected by front connection means 51 to agenerally L-shaped, rigid support member 51 which has one leg thereofrotatably mounted on the cross brace between the front legs 33.

The illustrated structure will now be described with some particularity,after which the operation of the device will be considered.

The rear bracket 49, which connects the rear end of the tablet arm 25 tothe section 23 in the illustrated device, is shown best in FIG. 13, andincludes a fixed plate 52 which is riveted, welded or similarly securedto the left side of the fname 23 (as viewed in the drawings). Pivotal-1yconnected to the fixed plate 52, as by a rivet 53, for rotation about agenerally horizontal axis, is first section 55 of a generally L-shapedplate or angle 54, having a second section designated 56. Hinged alongits edge to the outer edge of section 56 by means of a hinge pin 57 is aplate 58 which is suitably securely fixed to the underside of the tabletarm 25, as by means of screws (not shown) passing through the holes 59provided in plate 58.

This construction of the rear support bracket 49 provides firm, solidsupport for the rear end of the tablet arm 25 when the arm is beingused, contributing to the overall stability and elfective performance ofthe writing surface. In particular, when the arm 25 is in the raisedposition, as shown in FIG. 1, the plate 58 is folded back upon section56 of plate 54 to provide a relatively broad support surface for thearm. This broad support surface tends to eliminate wobble or tilting andprovides a firmer support for the rearward end of the arm 25.

The illustrated support member 51 (FIGS. 1-4) is an elongated, generallytubular, L-shaped part having legs or sections 60 land 61. Member 51 ismounted with section 60 disposed with its axis generally horizontal andparallel with the cross brace 35, and With section 61 extending upwardlyin a generally vertical direction from the end of section 60, on theleft side of the chair 21 as viewed in FIGS. 13. Horizontal section 61is rotatably received within (one of which is shown in detail in FIG.12) which are fixed upon the forward face of the cross brace 35. Eachbearing 62 is solidly fixed to the cross brace 35 by a pair of rivets,bolts or the like (not shown) which pass through spaced holes 62'provided in the bearings. Also, the cylindrical bearing surface, whicheach bearing 62 provides, extends for a substantial length (indicated byL in FIG. 12) along the horizontal section 60. Thus, the two spacedapart bearings 62 provide firm, steady and rigid support for the supportmember 51.

Vertical section 61 has an angularly bent portion 63 provided at itslower end to allow section 61 to assume a position adjacent the chairlegs (as shown in FIGS. 2 through 4), and the latter is connected at itsupper end to the tablet arm 25. A brace or strap 64 in the form of atube of metal or the like is fixedly connected between intermediatepoints on the two sections 60 and 61 of the support member. The strap 64provides reinforcement, and also provides a stop to the rearwardpivoting of the support member 51 in the bearings 62, as shown in FIG.2. The section 61 is also provided with a stop pin 48 whose functionwill be explained below.

Now to describe the front connection means between the tablet arm 25 andthe support member 51 in the illusa pair of spaced apart mountingsbearings 62 trated device. As shown in FIGS. 5 through 7, the tubularvertical section 61 is provided with a sleeve bracket 67 (shown indetail in FIG. 11), having a lower sleeve section 66 which slidablyengages the Vertical section 61, and an upper, U-s'haped section 65,which extends around and beyond section 61, so as to provide a pair ofspaced apart vertical plates 69. I

There is a slot 68 provided in the bight of U-shaped section 65, whichslot extends downwardly from the upper edge of the section 65. The upperend of the tubular vertical section 61 is provided with an end plug 70(FIG. 5) which is secured in place by a pin or nivet 68' having anenlarged head 71. The pin 68' is positioned so as to enter slot 68 whensleeve bracket 67 moves upwardly relative to vertical section 61 intothe relative positions shown in FIG. 5, the arm 25 thereby beingpositioned in its raised position as seen best in FIG. 1. In thatposition, the shank of the pin 68 engages the bottom of the slot 63 toprevent the bracket 67 from becoming disengaged from the verticalsection 61, while the head 71 of the pin 68 overlaps the edges of theslot 68. The seating of the pin 68 within the slot 68 and theoverlapping of the head 71 aid in providing firm and sturdy supportbetween the bracket 67 and the section 61, and so contribute to theoverall stability of the structure when it is in the raised position(FIG. 1).

The rearward portion of the lower edge of the bracket 67 is providedwith a pair of downward extensions 48 and 43". Extension 48 ispositioned to engage the stop pin 43 on the vertical section 61, whenthe device is in the lowered position shown in FIG. 6, to prevent arm 25from swinging outwardly from the position generally parallel to the sideof the chair shown in FIG. 2. Extension 48 is circumferentially spacedfrom extension 48', allowing rotation of the arm inwardly of the chairto the position shown in FIGS. 3 and 4, at which place extension 18"acts as a stop against further rotation in that direction.

A generally U-shaped double pivot bnacket 72 (shown in detail in FIG.10'), having an intermediate portion 73 and a pair of spaced apartvertical plates 74, is disposed, as best seen in FIG. 7, with itsvertical plates 74 positioned immediately outwardly of and pivotallyconnected to the vertical plates 69 of the sleeve bracket 67. As seen inFIG. 7, a suitable pivot pin, shaft or rod 76, having an enlarged head75 on one end and a threaded portion 77 at the other end to receive anut 78, passes through aligning apertures in the vertical plates 6 and74 to connect the brackets 67 and 72 for rotational movement relative toone another about the axis of that pin 76. The axis of the pivot pin 76is in substantial alignment with the axis of the pivot hinge 57 of therear connection bracket 49 to provide a common axis for arm 25 to tiltor rotate about as will be further explained. The axis of the pivot pin76 is also disposed generally perpendicular to and spaced-apart from thelongitudinal axis of the elongated vertical section 61. The bracket '72has a pair of vertical slots 79* extending into its center portion 73.These slots 79 are positioned to receive a pair of cars or extensions 80on the lower ends of the vertical plates 69 when the arm is moved to thevertical position shown in FIG. 6.

A hollow cylindrical roller spacer or sleeve 81 is rotatably disposedabout the pivot pin 76 and extends between the vertical plates 69 of thesleeve bracket 67. The outer surface of the sleeve 81 serves as apositioning roller, having a groove 81. which extends around itscircumference and is positioned to engage the vertical section 61, asseen best in FIG. 7, to guide the bracket 67 at its upper end formovement relative to .the section 61. The sleeve 81 also aids inmaintaining the proper spacing and disposition 'of the spaced-apartvertical plates 69 and '74.

The pressure responsive locking or holding means 27 of the illustrateddevice, shown in FIG. 8, includes a hollow, cylindrical tube or housing83 extending between the plates 69 of bracket 67 at a location below thepivot pin 76. The tube 83 extends through opposed apertures in theplates 69 and is secured in that position to provide an open passagewaybetween the plates 69. A pair of ball-bearings 85 are received in thepassageway of the tube 83, and are urged outwardly in oppositedirections by a small coil spring 87 positioned between them within thetube 8-3. The ball-bearings 85 are retained within the tube 83 by theinner surfaces of the plates 74 of the bracket 72, which surfacesoverlay the openings to the passageway. These plates 74- are eachprovided with an outwardly curved, generally circular depression 8-9.The two depressions 89 are positioned generally opposite from oneanother and are located relative to the pivot pin 76 so as to align withthe tube 83- and receive the ball-bearings 85 (FIG. 8) when the partsare in the respective positions shown in FIG. 5, wherein the arm 25 isin its raised position. The spring 87 urges the ballbearings 85outwardly and into the depressions 8 9, thus maintaining the partsreleasably fixed in that position until sufiicient pressure tending torotate the bracket 72 in a counter-clockwise direction (as seen in FIG.5) moves the ball-bearings 85 inwardly against the spring 87 to allowthe rotation.

A second pair of similarly constructed, opposed depressions 90 in theplates 74- serve to releasably lock the tablet arm 25 in the tiltedposition. As the arm moves from the position shown in FIG. 5 to thattilted position, the ball-bearings 85 are in rolling contact with theinner surface of the plates 74 so as to retain them within the tube 83-.The two positions are extreme positions, further rotation in eitherdirection about pin 76 being restricted as will be described.

As shown in FIGS. 5, 6 and 9, the illustrated bracket 72 is pivotallyconnected to a flanged housing 93, which is fixed to the underside ofthe tablet arm 25, for relative rotation therebetween about an axiswhich is generally perpendicular to the upper surface of the arm 25 andintersects the axis provided by pivot pin 76. More particularly, the midor intermediate portion 73 of the bracket 72 includes a generallycircular, centrally disposed hub 95 (FIG. The housing 93' has a mainwall 97 disposed generally parallelly spaced from the undersunface ofthe arm 25, and having a peripheral skirt or flange 99 which engages theu-ndersurface and is fixed thereto as by means of screws 100. The mainwall 97 has a central, circular opening 101 which receives the hub 95 ofthe bracket 72 for rotation therein. The main wall 97 adjacent theopening 101 is offset to provide a circular shoulder 102 which maintainsthe part of the intermediate wall 73 of the bracket 72 which isoutwardly of the shoulder 102, spaced slightly from the main Wall 97.The hub 95 is held in the opening 101 by a formed, generally discashapedspring 103 which is disposed centrally over the hub 95 and connected toit by means of a centered rivet 105, having its shank passing throughaligned apertures in the hub 95 and the spring 103 and its enlarged endsdisposed on either side thereof. A disc-shaped washer 107 is disposedinside the housing 93 around the opening 101. The disc spring 103 has alarger diameter than the opening 101 so that its marginal portion abutsthe washer 107. The spring 103 is formed so as to tend to position itscenter portion away from the washer 107. The rivet 105 restricts thiscenter portion of the spring 103, the result being that the spring 103urges the bracket 72 into abutting engagement with the raised shoulder102 of the housing 93. The spring 103 thus cooperates with the otherparts to act as a retarding means, i.e., create abutting, high frictioncontact to retard the relative rotation between the bracket 72 and thehousing 93 to prevent falling of the arm. In addition to its retardingfunction, this spring structure will compensate for wear to the partscaused by the relative movement therebetween, and serves to reducewobble in the device. a

Now to consider the operation of the device. FIG. 1 shows the chair 21extended, and the tablet arm 25 is in the raised position in a generallyhorizontal plane and the tablet arm support section 61 is in a generallyvertical extending position. The rear support bracket 49, together withthe front connection means 50 and the support member 51, provide firm,solid, stable support tor the tablet arm 25 to provide the desiredwriting surface. Since the pivot pin 76 is positioned well toward theoutside of the chair 21, downward pressure on the writing surface of thearm incident to its normal use will urge the arm downwardly against itssupports to provide a solid, steady surface. The pressure responsivemeans 27 maintains the arm 25 in the desired position, and further tendsto remove Wobble.

To lower the arm 25, the user may simply grasp it by its inner edge andtilt or rotate it about the generally horizontal axis defined by pivotpin 76 ot the front connection means 50 and the hinge pin 57 of the rearsupport bracket 49, by merely applying suflicient pressure against thereleasable, pressure responsive, locking or holding means 27 to releaseit, i.e., disengage the ball bearings 05 item the depressions 89. Thearm 25 is thus tilted or rotated to a position wherein its upper surfacelies in a generally vertical plane. The engagement of the ears in thebottoms of the slots 79 of the bracket 72 serves to prevent over tiltingof the arm. The arm is maintained in the vertical position by theengagement of the ball bearings with the depressions which additionallyserve to reduce wobble.

Then the front end of the arm 25 may be lowered to the position shown inFIG. 2: the arm 25 pivots or swings about rivet 53 of the rear supportbracket 49, sleeve bracket 67 slides relative to the vertical section 61or the support member 51, said section 61 moving through an are asmember 51 pivots in mounting bearings 62, and the bracket 72 pivotsrelative to the housing 93. As already pointed out, this last relativepivoting motion is retarded by the spring 103, thereby slowing down thismovement to prevent the arm 25 from falling suddenly and rapidly tocause a noise or to possibly injure someone. In the illustrated chair21, the downward swing of the arm 25 is limited by the strap 64 engaginga front leg 33 of the chair (FIG. 1), and by the engagement of stop pin48 with the lower edge of the sleeve bracket 67, as seen best in FIG. 6.When the arm 25 is in this lowered position, it is out of the way andthe chair 21 may be used as any other chair. It may be noted that thevertical section 61 moves through a relatively small angle in going fromits position in FIG. 1 to its position in FIG. 2.

If it is desired to store or carry the chair 21, the legs 33 and 37 arebrought together, raising the seat 41 so that the section 23 (includingthe front legs 33), the seat 4-1, and the rear legs 37 are all ingeneral alignment with one another as shown in FIG. 4. Then, the arm 25may be rotated to lie generally flush against the chair, as shown inFIGS. 3 and 4, the plate 58 of the rear support bracket 49 pivotingabout hinge pin 57, while the sleeve bracket 67 and the parts connectedto it are rotating about vertical section 61. In this latter position,the chair 21 is ready for transportation or storage.

Thus, the illustrated chair has a firmly and stably supported tablet armwhich may be readily lowered in direct repsonse to pressure. It requiresno preliminary step such as unlatching, etc. The structure provides firmstable support for the arm at all times, and particularly when it is inthe raised or use position. The retarding means eliminate the noise offalling arms and guard against injury. The operation of the arm is easyand uncomplicated, and requires a minimum of time and also a minimum ofspace.

Obviously many modifications and changes may be made to the illustratedchair structure without departing from the spirit and scope of theinvention. Various teatures of the invention are set forth in thefollowing claims.

I claim:

-1. In combination with a chair including a chair frame providing a pairof front legs, a pair of rear legs, and a back rest, a tablet armassembly comprising, a tablet arm, a pivotal connection securing arearward portion of said tablet arm to said back rest adjacent one sideof the chair for relative movement about a pair of transverse axes, andmeans connecting a forward portion of said tablet arm to said framecomprising'a support member carried at its lower end by the frame forswinging movement through a generally vertical plane along said one sideof the chair from a generally vertical position and in a directiontoward said back rest to a rearwardly inclined position, and a universalconnection between the tablet arm and said support member including abearing means on the underside of said tablet arm, a yoke-like elementconnected with said bearing means for pivotal movement about an axisdisposed at right angles to the plane of said tablet arm, a sleeveelement slidably engaging said support member for movement axiallythereof and connected with said yoke-like element for relative pivotalmovement about an axis transverse to and spaced from the axis of thesleeve and support member, whereby said tablet arm may be rotated aboutsaid transverse axis of said universal connection and one of said axesof said rearward pivotal 25 connection to move between agenerallyhorizontal position of use and a generally vertical positionalong said one side of the chair, and when in said generally verticalposition the tablet arm may be moved vertically downward about the othertransverse axis of said rearward pivotal connection and said axis ofsaid bearing means to cause said sleeve to slide along said supportmember and place said tablet arm in its lowered position alongside thechair with said support member disposed in its rearwardly inclinedposition with respect to its connection with said frame, and a biasingmeans in position to urge the adjoining surfaces of said bearing meansand yokelike element together to resist relative rotation therebetween,whereby said tablet arm is maintained in any selected position alongsaid support member when the tablet arm is positioned in said generallyvertical position along said one side of the chair.

2. The combination set forth in claim 1, wherein said front and rearlegs are pivotally interconnected intermediate their ends to permitfolding of said chair, a cross brace extends between said pair of frontlegs adjacent the lower end portions thereof, and said support memberfor the tablet arm includes a lower transverse portion swingably mountedon said cross brace.

References Cited in the file of this patent UNITED STATES PATENTS2,664,943 Clarin Jan. 5, 1954 2,954,073 Junkunc Sept. 27, 1960 3,024,065Eves et al. Mar. 6-, 1962

1. IN COMBINATION WITH A CHAIR INCLUDING A CHAIR FRAME PROVIDING A PAIROF FRONT LEGS, A PAIR OF REAR LEGS, AND A BACK REST, A TABLET ARMASSEMBLY COMPRISING, A TABLET ARM, A PIVOTAL CONNECTION SECURING AREARWARD PORTION OF SAID TABLET ARM TO SAID BACK REST ADJACENT ONE SIDEOF THE CHAIR FOR RELATIVE MOVEMENT ABOUT A PAIR OF TRANSVERSE AXES, ANDMEANS CONNECTING A FORWARD PORTION OF SAID TABLET ARM TO SAID FRAMECOMPRISING A SUPPORT MEMBER CARRIED AT ITS LOWER END BY THE FRAME FORSWINGING MOVEMENT THROUGH A GENERALLY VERTICAL PLANE ALONG SAID ONE SIDEOF THE CHAIR FROM A GENERALLY VERTICAL POSITION AND IN A DIRECTIONTOWARD SAID BACK REST TO A REARWARDLY INCLINED POSITION, AND A UNIVERSALCONNECTION BETWEEN THE TABLET ARM AND SAID SUPPORT MEMBER INCLUDING ABEARING MEANS ON THE UNDERSIDE OF SAID TABLET ARM, A YOKE-LIKE ELEMENTCONNECTED WITH SAID BEARING MEANS FOR PIVOTAL MOVEMENT ABOUT AN AXISDISPOSED AT RIGHT ANGLES TO THE PLANE OF SAID TABLET ARM, A SLEEVEELEMENT SLIDABLY ENGAGING SAID SUPPORT MEMBER FOR MOVEMENT AXIALLYTHEREOF AND CONNECTED WITH SAID YOKE-LIKE ELEMENT FOR RELATIVE PIVOTALMOVEMENT ABOUT AN AXIS TRANSVERSE TO AND SPACED FROM THE AXIS OF THESLEEVE AND SUPPORT MEMBER, WHEREBY SAID TABLET ARM MAY BE ROTATED ABOUTSAID TRANSVERSE AXIS OF SAID UNIVERSAL CONNECTION AND ONE OF SAID AXESOF SAID REARWARD PIVOTAL CONNECTION TO MOVE BETWEEN A GENERALLYHORIZONTAL POSITION OF USE AND A GENERALLY VERTICAL POSITION ALONG SAIDONE SIDE OF THE CHAIR, AND WHEN IN SAID GENERALLY VERTICAL POSITION THETABLET ARM MAY BE MOVED VERTICALLY DOWNWARD ABOUT THE OTHER TRANSVERSEAXIS OF SAID REARWARD PIVOTAL CONNECTION AND SAID AXIS OF SAID BEARINGMEANS TO CAUSE SAID SLEEVE TO SLIDE ALONG SAID SUPPORT MEMBER AND PLACESAID TABLET ARM IN ITS LOWERED POSITION ALONGSIDE THE CHAIR WITH SAIDSUPPORT MEMBER DISPOSED IN ITS REARWARDLY INCLINED POSITION WITH RESPECTTO ITS CONNECTION WITH SAID FRAME, AND A BIASING MEANS IN POSITION TOURGE THE ADJOINING SURFACES OF SAID BEARING MEANS AND YOKELIKE ELEMENTTOGETHER TO RESIST RELATIVE ROTATION THEREBETWEEN, WHEREBY SAID TABLETARM IS MAINTAINED IN ANY SELECTED POSITION ALONG SAID SUPPORT MEMBERWHEN THE TABLET ARM IS POSITIONED IN SAID GENERALLY VERTICAL POSITIONALONG SAID ONE SIDE OF THE CHAIR.